Quasi-Continuous Photon Detection via Dynamic Bias Control

The patent applies periodic gating to the avalanche photodiode, switching it between active detection mode and reset mode. During the reset phase, excess carriers are cleared, reducing dark counts and noise. The periodic gating allows the detector to recover between measurement cycles, maintaining high sensitivity while suppressing noise accumulation.

The patent extracts and removes excess charge carriers from the depletion region through controlled reset phases. By actively clearing accumulated carriers that cause noise and dark counts, the system maintains high detection sensitivity while reducing harmful noise effects. The reset mechanism selectively removes unwanted carriers without affecting the detection capability.

The patent implements dynamic bias voltage control, adjusting the reverse bias voltage on the avalanche photodiode based on the detected signal level. For high light intensities, the bias is reduced to prevent saturation and maintain linearity. For single photon events, the bias is optimized for maximum detection efficiency. This dynamic adjustment enables both high intensity handling and precise photon number resolution.

The patent changes the operating parameters of the avalanche photodiode, specifically the reverse bias voltage and integration time, to optimize performance for different light intensity levels. By adjusting these parameters dynamically, the system maintains accurate photon number resolution across a wide dynamic range, from single photons to high intensity pulses.

The patent implements periodic gating with alternating active and reset phases. During reset phases, noise and excess carriers are cleared, preventing accumulation. The periodic cycle allows continuous operation at high throughput while systematically removing noise between measurement cycles, maintaining signal quality over extended operation.

The patent achieves continuous detection capability through rapid periodic gating cycles. The active detection phase continuously monitors for photons, while the reset phase quickly clears noise. This continuous cycling maintains high productivity without allowing noise to accumulate, as the reset occurs frequently enough to prevent noise buildup between cycles.